library/padlock.c

   1 /*
   2  *  VIA PadLock support functions
   3  *
   4  *  Based on XySSL: Copyright (C) 2006-2008  Christophe Devine
   5  *
   6  *  Copyright (C) 2009  Paul Bakker <polarssl_maintainer at polarssl dot org>
   7  *
   8  *  All rights reserved.
   9  *
  10  *  Redistribution and use in source and binary forms, with or without
  11  *  modification, are permitted provided that the following conditions
  12  *  are met:
  13  *
  14  *    * Redistributions of source code must retain the above copyright
  15  *      notice, this list of conditions and the following disclaimer.
  16  *    * Redistributions in binary form must reproduce the above copyright
  17  *      notice, this list of conditions and the following disclaimer in the
  18  *      documentation and/or other materials provided with the distribution.
  19  *    * Neither the names of PolarSSL or XySSL nor the names of its contributors
  20  *      may be used to endorse or promote products derived from this software
  21  *      without specific prior written permission.
  22  *
  23  *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  24  *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  25  *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  26  *  FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  27  *  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  28  *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
  29  *  TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  30  *  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  31  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  32  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  33  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  34  */
  35 /*
  36  *  This implementation is based on the VIA PadLock Programming Guide:
  37  *
  38  *  http://www.via.com.tw/en/downloads/whitepapers/initiatives/padlock/
  39  *  programming_guide.pdf
  40  */
  41
  42 #include "tropicssl/config.h"
  43
  44 #if defined(TROPICSSL_PADLOCK_C)
  45
  46 #include "tropicssl/aes.h"
  47 #include "tropicssl/padlock.h"
  48
  49 #if defined(TROPICSSL_HAVE_X86)
  50
  51 #include <string.h>
  52
  53 /*
  54  * PadLock detection routine
  55  */
  56 int padlock_supports(int feature)
  57 {
  58         static int flags = -1;
  59         int ebx, edx;
  60
  61         if (flags == -1) {
  62 asm("movl  %%ebx, %0           \n" "movl  $0xC0000000, %%eax  \n" "cpuid                     \n" "cmpl  $0xC0000001, %%eax  \n" "movl  $0, %%edx           \n" "jb    unsupported         \n" "movl  $0xC0000001, %%eax  \n" "cpuid                     \n" "unsupported:              \n" "movl  %%edx, %1           \n" "movl  %2, %%ebx           \n":"=m"(ebx),
  63                     "=m"
  64                     (edx)
  65 :                   "m"(ebx)
  66 :                   "eax", "ecx", "edx");
  67
  68                 flags = edx;
  69         }
  70
  71         return (flags & feature);
  72 }
  73
  74 /*
  75  * PadLock AES-ECB block en(de)cryption
  76  */
  77 int padlock_xcryptecb(aes_context * ctx,
  78                       int mode,
  79                       const unsigned char input[16],
  80                       unsigned char output[16])
  81 {
  82         int ebx;
  83         unsigned long *rk;
  84         unsigned long *blk;
  85         unsigned long *ctrl;
  86         unsigned char buf[256];
  87
  88         rk = ctx->rk;
  89         blk = PADLOCK_ALIGN16(buf);
  90         memcpy(blk, input, 16);
  91
  92         ctrl = blk + 4;
  93         *ctrl = 0x80 | ctx->nr | ((ctx->nr + (mode ^ 1) - 10) << 9);
  94
  95 asm("pushfl; popfl         \n" "movl    %%ebx, %0     \n" "movl    $1, %%ecx     \n" "movl    %2, %%edx     \n" "movl    %3, %%ebx     \n" "movl    %4, %%esi     \n" "movl    %4, %%edi     \n" ".byte  0xf3,0x0f,0xa7,0xc8\n" "movl    %1, %%ebx     \n":"=m"(ebx)
  96 :           "m"(ebx), "m"(ctrl), "m"(rk), "m"(blk)
  97 :           "ecx", "edx", "esi", "edi");
  98
  99         memcpy(output, blk, 16);
 100
 101         return (0);
 102 }
 103
 104 /*
 105  * PadLock AES-CBC buffer en(de)cryption
 106  */
 107 int padlock_xcryptcbc(aes_context * ctx,
 108                       int mode,
 109                       int length,
 110                       unsigned char iv[16],
 111                       const unsigned char *input,
 112                       unsigned char *output)
 113 {
 114         int ebx, count;
 115         unsigned long *rk;
 116         unsigned long *iw;
 117         unsigned long *ctrl;
 118         unsigned char buf[256];
 119
 120         if (((long)input & 15) != 0 || ((long)output & 15) != 0)
 121                 return (1);
 122
 123         rk = ctx->rk;
 124         iw = PADLOCK_ALIGN16(buf);
 125         memcpy(iw, iv, 16);
 126
 127         ctrl = iw + 4;
 128         *ctrl = 0x80 | ctx->nr | ((ctx->nr + (mode ^ 1) - 10) << 9);
 129
 130         count = (length + 15) >> 4;
 131
 132 asm("pushfl; popfl         \n" "movl    %%ebx, %0     \n" "movl    %2, %%ecx     \n" "movl    %3, %%edx     \n" "movl    %4, %%ebx     \n" "movl    %5, %%esi     \n" "movl    %6, %%edi     \n" "movl    %7, %%eax     \n" ".byte  0xf3,0x0f,0xa7,0xd0\n" "movl    %1, %%ebx     \n":"=m"(ebx)
 133 :           "m"(ebx), "m"(count), "m"(ctrl),
 134             "m"(rk), "m"(input), "m"(output), "m"(iw)
 135 :           "eax", "ecx", "edx", "esi", "edi");
 136
 137         memcpy(iv, iw, 16);
 138
 139         return (0);
 140 }
 141
 142 #endif
 143
 144 #endif